AI Agent Memory Systems

Why Memory Matters for AI Agents

Without memory, AI agents are stateless - every conversation starts fresh. Memory enables:

Personalization based on past interactions

Learning from mistakes

Maintaining context across sessions

Building relationships over time

Types of Memory

1. Working Memory (In-Context)

Short-term memory stored directly in the conversation context:

python
messages = [
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "My name is Alice"},
    {"role": "assistant", "content": "Nice to meet you, Alice!"},
    {"role": "user", "content": "What's my name?"},  # Agent can answer from context
]

2. Episodic Memory

Records of past interactions stored in a database:

python
class EpisodicMemory:
    def __init__(self, db):
        self.db = db
    
    def store(self, user_id, interaction):
        self.db.insert({
            "user_id": user_id,
            "timestamp": datetime.now(),
            "summary": interaction.summary,
            "key_facts": interaction.extract_facts()
        })
    
    def retrieve(self, user_id, query, k=5):
        return self.db.semantic_search(
            query=query,
            filter={"user_id": user_id},
            limit=k
        )

3. Semantic Memory (Knowledge Base)

Factual knowledge stored as embeddings:

python
from langchain.vectorstores import Chroma
from langchain.embeddings import OpenAIEmbeddings
semantic_memory = Chroma(
    embedding_function=OpenAIEmbeddings()
)
Store facts
semantic_memory.add_texts([
    "Alice prefers Python over JavaScript",
    "Alice works at TechCorp as a data scientist",
    "Alice is interested in machine learning"
])
Retrieve relevant context
results = semantic_memory.similarity_search(
    "What programming language does the user prefer?"
)

Memory Management

As memories accumulate, you need strategies to:

Summarize old conversations

Prioritize important memories

Forget irrelevant information

Handle contradictions

Privacy Considerations

Always implement memory with user consent and provide options to view/delete stored memories.